Abit AX5 Instruction Booklet page 35

Installing the Mainboard
¡i
Computer
Knowledge
According to the standards defined by JEDEC, there are a lot of
different types of specifications for 168-pin DIMM sockets. Here
are the possible types:
These types of DIMM modules differ not only by the electrical
design, but also by their architecture. So, if you buy different
types of DIMM modules, you will not be able to insert them in
the DIMM sockets. Currently, the standard for PC is 3.3V
UNBUFFERED DIMM, which is the standard supported by this
series.
After installing the DRAM, the BIOS of the mainboard will automatically
detect the size of the memory installed on the mainboard. Below is a list of all
the possible situations:
Scenario 1: You use only 72-pin SIMM modules:
l
l
l Memory modules supported: 1Mx32 ¡i 4M ¡j , 2Mx32
l
Scenario 2: You use only 168-pin DIMM modules:
l
l Support possible for single density or double density memory
modules.
l Memory modules supported: 1Mx64 ¡i 8M ¡j , 2Mx64
¡i 16M ¡j , 4Mx64 ¡i 32M ¡j , 8Mx64 ¡i 64M ¡j
or 16Mx64 ¡i 128M ¡j .
l DIMM1 is the first pair, DIMM2 is the second pair. Usually,
you first insert modules in DIMM1 socket, than in DIMM2
socket, but it is possible to do the reverse.
l You can also directly refer to table 2-2.
168-pin DIMM modules specifications ¡j
l 3.3V UNBUFFERED DIMM
l 3.3V BUFFERED DIMM
l 5V UNBUFFERED DIMM
l 5V BUFFERED DIMM
The maximum memory size is 256M bytes.
Support possible for single density or double density memory
modules.
¡i 8M ¡j , 4Mx32 ¡i 16M ¡j , 8Mx32 ¡i 32M ¡j
or 16Mx32 ¡i 64M ¡j .
You can also directly refer to table 2-1.
The maximum memory size is 256M bytes.
2-19